白细胞介素-1β在气道重塑中作用的实验研究

Effect of interleukin-1β on airway remodeling

目的研究前炎症因子白细胞介素-1β(IL-1β)对气道上皮细胞(BEC)转化生长因子-β1(TGF-β1)的调控,以探讨其在气道重塑中的作用。方法选择原代分离新西兰种白兔的BEC作为研究对象,体外培养,将培养细胞随机分4组:对照组和IL-1β处理A、B、C组。A、B、C组分别加入终浓度为0·1、1、10mg/L的IL-1β作用24h,对照组加入等量无血清培养液,采用原位杂交和免疫细胞化学染色的方法观察各组TGF-β1mRNA和蛋白的表达。结果TGF-β1mRNA和蛋白表达IL-1β处理A组(0·162±0·023、0·156±0·003)、B组(0·318±0·013、0·614±0·020)、C组(0·644±0·016、0·917±0·050)均较对照组(0·098±0·020、0·138±0·009)显著增强,差异有统计学意义(P均<0·01),A、B、C组两两比较差异有统计学意义(P均<0·01),其中IL-1β处理C组TGF-β1mRNA和蛋白表达均最强,随IL-1β浓度的增加,TGF-β1mRNA和蛋白表达呈剂量依赖性增加。结论前炎症因子IL-1β可上调气道上皮细胞TGF-β1的表达,当过度调节后可导致气道重塑。

Objective To evaluate the effect of interleukin-1β（IL-1β） on the expression of transforming growth factor （TGF）-β1 in the bronchial epithelial cell and the effect of IL-1β on airway remodeling. Methods Primary bronchial epithelial cells were obtained from rabbit trachea and cultured in vitro. After cell growing up to colony, it was divided randomly into 4 groups：normal control group, IL-1β treated groups A,B and C, stimulated by IL-1β（0.1,1,10 mg/L, repectilvdy）for 24 hours, and the normal control group incubated with equal serum free conditioned medium. Cellcoated dishes were attained, then the expression of TGF-β1 was measured by in situ hybridization and immunocytochemistry. Results ①Cell morphology and identification： Bronchial epithelial cells grew in a typical epithelial fashion forming a fully confluent monolayer with cobblestone appearance and its characteristics were identified by positive immunostaining of keratin. ②Effect of IL-1β on expression of TGF-β1 mRNA： The expression of TGF-β1 mRNA in IL-1β treated groups A（0. 162 ± 0. 023）, B（ 0. 318 ± 0. 013 ）and C（ 0. 644 ± 0. 016 ）was significantly higher than that in normal control group（0. 098 ± 0. 020）（ P〈 0.01 ）, and there was significant difference in groups A, B and C in terms of TGF-β1 mRNA expression （ P 〈 0.01 ）. ③Effect of IL- 1β on expression of TGF-β1 protein： The expression of TGF-β1 protein in IL-1β treated groups A（0. 156± 0. 003） ,B（0. 614 ± 0. 020） ,and C（0. 917± 0. 050）was significantly higher than that in normal control group （0.138 ± 0. 009 ） （ P 〈 0.01 ）, and there was significant difference in groups A, B and C in terms of TGF-β1 protein expression （P〈0.01）. Conclusion Pre-inflammatory cytokine IL-1β can upregulate the expression of TGF-β1 mRNA and protein in bronchial epithelial cell. The ability of IL-1β to modulate TGF-β1 release may contribute to both abnormal airway repair and development of airway remodeling.